Tappet guide extraction and cam bushes

**brookvale** · 23rd March 2023, 08:33 AM

Hi guys. Almost there for my IIA block and head to go for professional cleaning and machining.
Crankshaft main and big end bearings all look quite clean - shells not scored or worn, just minor wear marks.
Camshaft bearings and lobes, and the bushings, mostly look not too shabby - just some minor wear marks, no scoring at all.
Had heart attack when noticed one cam lobe looked totally worn away... oops! - was the fuel pump lobe

Then noticed cam drive sprocket end bearing had major section missing - not worn away but a manufacture defect I think.
A little late for a warranty replacement!!

Nothing on bushing to show it has been destroying it but there are some odd marks.
Rest of cam bearings look fine.

Block water galleries looked OK, some rustiness and plenty flakes which I blew out with comp. air until I found drain plug hole was blocked with fine rust. had to chip away at it but can't get to reach cylinder spaces.

Q1: What's your expert view on the 'defective' cam bearing?
Should I replace cam and fit new bushings?
I've no idea of mileage but rest of bearings look fine as do the cranks' . They suggest engine not a total worn out beast.
Almost keen to keep using this cam shaft - it has lasted since 1962-3 or 4

PXL_20230315_214930807.jpg PXL_20230315_214958542.jpg PXL_20230315_223252130.jpg PXL_20230315_225620881.jpg PXL_20230315_225635391.jpg PXL_20230322_220031052.jpg PXL_20230322_220045753.jpg PXL_20230322_220122093.jpg PXL_20230322_220142060.jpg

Q2: Tappet guides
I don't have the LR special tool but could make something similar if need be.
Any other options for removal?
Again don't want blasting/cleaning to ruin them.
Could they stay in during cleaning etc?

cheers. Neil

**JDNSW** · 23rd March 2023, 12:20 PM

Q1 I think the fact that the faulty cam journal has survived this long suggests it probably will indefinitely. The journals and bearings on the camshaft are much larger than is needed for the load on them, because the cams have to fit through the bearings, so in that sense they are over-engineered.

Q2 The tool looks pretty simple to make (it is essentially a slide hammer), but I note that my manual says the tool will make it easier if the guides cannot be removed by hand, suggesting that if you are lucky you won't need it.

**brookvale** · 23rd March 2023, 12:35 PM

cheers John. My thoughts same re cam journal but wanted some reassurance

Odd that the book says "use tool XYZ" if cannot by hand" for tappet guides - none of my guides are hand-loose enough to be be pulled out so some jiggery pokery needed
to get them out. probably jammed by old oil/etc

One day I must have a chat with the chap who wrote the book

Neil

**JDNSW** · 23rd March 2023, 06:42 PM

Originally Posted by brookvale

c.....
One day I must have a chat with the chap who wrote the book

Neil

Considering the engine went on sale in 1958, and presumably the "book" was written before then, even if the author was a youngster of around 20 at the time, he would be getting on a bit by now. I suggest that if you want a chat with him, you need to start tracking him down, and be prepared for it to already be too late!

**brookvale** · 26th March 2023, 01:00 PM

Surprise surprise! Got in touch with Turners UK with the query re cam journal.
Essentially they said "you idiot, it was made like that to let oil to pass through... they are all like that in these engines".
So there you go..
But for life of me can't recall seeing same thing on a IIA engine wot I rebuilt 10 yrs ago - memories fade !
Neil

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